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opt_dff: fix sequence point copy paste bug 

Newer GCCs emit the following warning for opt_dff:

    passes/opt/opt_dff.cc:560:17: warning: operation on ‘ff.Yosys::FfData::has_clk’ may be undefined [-Wsequence-point]
      560 |      ff.has_clk = ff.has_ce = ff.has_clk = false;
          |      ~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Which is correct: the order of whether the read or write of has_clk
occurs first is undefined since there is no sequence point between them.

This is almost certainly just a typo/copy paste error and objectively
wrong, so just fix it.

Signed-off-by: Austin Seipp <aseipp@pobox.com>
This commit is contained in:
Austin Seipp 2022-01-04 10:49:54 -06:00 committed by Marcelina Kościelnicka
parent 493b5e03e7
commit b022fe61a7
1 changed files with 1 additions and 1 deletions
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2
passes/opt/opt_dff.cc
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@ -557,7 +557,7 @@ struct OptDffWorker
// The D input path is effectively useless, so remove it (this will be a const-input D latch, SR latch, or a const driver).
log("Handling D = Q on %s (%s) from module %s (removing D path).\n",
log_id(cell), log_id(cell->type), log_id(module));
ff.has_clk = ff.has_ce = ff.has_clk = false;
ff.has_clk = ff.has_ce = false;
changed = true;
}
}